No app field and locale is English. I have enough to write. Here's the article body:
You don't need an app for this
The most common mistake people make: they go hunting for a "screenshots to PDF" utility, or paste their captures into a Google Doc and export. On a Mac, Preview already does this — it ships with macOS, it works fully offline, and it gives you control over page order before you commit. No upload, no watermark, no subscription.
This guide shows three ways to combine screenshots into a PDF on Mac, from the quickest to the most precise. Pick based on how much you care about page order.
The fast way: open everything in Preview, then export
If you just want one PDF and the order doesn't have to be perfect on the first try:
1. In Finder, select all the screenshots you want (Shift-click for a range, Command-click to cherry-pick). 2. Double-click to open them. They land in a single Preview window with a thumbnail sidebar down the left. 3. Reorder by dragging thumbnails up or down in the sidebar. 4. Choose File > Export (or Export as PDF), set the format to PDF, name the file, and save.
That's the whole loop. One window, one export, one PDF. If the sidebar isn't showing, turn it on with View > Thumbnails.
The precise way: combine them like PDF pages
Preview treats screenshots and PDFs the same way in the thumbnail sidebar, which means you can assemble a document page by page — useful when you're stitching a tutorial, a bug report, or a receipt set in an exact sequence.
- Open one screenshot (or an existing PDF) in Preview, then choose View > Thumbnails.
- Drag any other image file directly into the thumbnail sidebar, releasing it exactly where you want that page to appear. Drop it between two thumbnails to insert in the middle, or at the bottom to append.
- Repeat for each screenshot. Command-click to select several thumbnails at once and move them as a block.
- When the order looks right, File > Export to PDF.
This is the same mechanism Preview uses to merge two PDFs — open both, show thumbnails in each, and drag pages from one sidebar into the other. Screenshots are just single-page sources in that flow.
Which method to use
| You want… | Use | Why | |---|---|---| | One PDF, fast, order roughly right | Open all → reorder → Export | Fewest steps; all images load at once | | Exact page order, inserting mid-document | Drag files into the thumbnail sidebar | Precise drop position per page | | To merge screenshots into an existing PDF | Show thumbnails in both → drag pages across | Same combine flow Preview uses for PDFs |
A few things that save you grief
- Order is set in the sidebar, not in Finder. However the thumbnails are stacked top-to-bottom is the page order you'll get. Fix it before exporting.
- Rename before you combine if order matters. Screenshots default to timestamped names; if you open a whole folder, Preview follows the Finder sort. Naming them
01,02,03first makes the sequence predictable. - Export, don't print-to-PDF, when you can. Exporting keeps the images crisp and avoids the extra margins a print dialog adds.
- It's all local. Nothing leaves your Mac, which matters when the screenshots contain anything you'd rather not upload to a web converter.
If your captures are HEIC rather than PNG/JPEG, convert them first — see batch convert HEIC to JPG on Mac. And if you'd rather script the whole thing for a folder of images, the macOS sips command-line guide covers the terminal route.